The goal of the proposed research is to study the vascular architecture of the dental pulp. The essential requirement for growth and function of any tissue or organ is the blood supply. The study of its structure and ability to respond to stimuli would provide information regarding tissue growth, function, response to physiologic and pathologic stimuli, and repair. Because of the frequent involvement of the tooth in dental disease and in its treatment, such information would have a direct impact on dental therapy. Research in this area has been hampered by the technical problems resulting from the encasement of this organ in calcified tissues. Anatomic analyses have resulted from histologic reconstructions and dye injection of the blood vessels viewed through the surrounding tissues that have been rendered transparent. However, the ability to study the vascular architecture under physiologic conditions without the interference of surrounding tissue has not been possible. The specific aim of this proposal is to develop the methodology for preparing methacrylate casts of the pulp vasculature using techniques that preserve the physiologic status at the time of perfusion. The previously described Murakami technique will be modified to employ a newly developed methacrylate solution that possesses low viscosity and a prolonged setting time that permits perfusion at sub-systolic pressures. Using this protocol, we will prepare castings under reproducable conditions and begin to study pulpal hemodynamics.